The makeup maven stepped out for her 19th birthday party at The Nice Guy in West Hollywood, California, on Sunday night wearing a lacy black catsuit, which she accessorized with a gilded belt to fully show off her hourglass figure.

The stunning skintight look -- and let's admit it, slightly shocking, even for this family -- gave us quite a bit of déjà vu.

While Kim, 35, was pregnant with her son, Saint, last year, she stepped out in a number of lacy looks, one more sheer than the next.

First, she bared her bump at Riccardo Tisci's first-ever stateside show for Givenchy during New York Fashion Week in September. The sheer illusion paneling of the black dress put her growing belly on full display and gave us very Madonna circa "Like a Virgin" vibes.

Two months later, Kim rocked an even sheerer number, once again by Givenchy, that totally resembles what Kylie dazzled in on her birthday -- a daring, see-through black lace jumpsuit, which she paired with a floor-length blazer, peep-toe heels, diamond choker and dramatic wine-colored lips.

Photo: Getty Images

They do say that imitation is the sincerest form of flattery! In fact, everything about Kylie's look has grown closer and closer to Kim's. Not only do they both have penchants for Balmain, their closet staples are nearly identical -- think a penchant for Balmain, plenty of bodysuits, neutral curve-hugging dresses, and low-cut black numbers. Or, sometimes they just straight up steal each other’s clothes, like that time they rocked the exact same beige Mikoh bikini last June.

Photo: Instagram

But it's not just their fashion sense that's similar -- their makeup looks pretty much mimic each other at this point.

Listen, when you've got someone like Kim teaching you how to take a selfie, you're bound to learn a thing or two.

Despite the copycat tendencies, Kylie actually explained that she's not trying to "steal Kim's throne" in a video posted to her app in January. "We're not in a competition. We're completely different people," she explained. "She's one of my biggest inspirations. That's not a secret. I look up to my sister. I don't think that's a weird thing… I do want to be Kim."

As for Kim, she admitted in June 2015 that Kylie was her mini-me, telling ET, "She is the best, you know? She's my little twin soul. She's such a free spirit, and I love that. She's the sweetest."

The two actually look so alike these days that you could barely tell who was who when Kim posted a side-by-side split of her and Kylie's faces to Instagram last year. Check out the eerie resemblance in the video below.